81950051 has 4 divisors (see below), whose sum is σ = 81998400. Its totient is φ = 81901704.

The previous prime is 81950041. The next prime is 81950053. The reversal of 81950051 is 15005918.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81950051 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81949996 and 81950023.

It is not an unprimeable number, because it can be changed into a prime (81950053) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21536 + ... + 25053.

It is an arithmetic number, because the mean of its divisors is an integer number (20499600).

Almost surely, 2^81950051 is an apocalyptic number.

81950051 is a deficient number, since it is larger than the sum of its proper divisors (48349).

81950051 is a wasteful number, since it uses less digits than its factorization.

81950051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48348.

The product of its (nonzero) digits is 1800, while the sum is 29.

The square root of 81950051 is about 9052.6267458677. The cubic root of 81950051 is about 434.3599182590.

Adding to 81950051 its reverse (15005918), we get a palindrome (96955969).

The spelling of 81950051 in words is "eighty-one million, nine hundred fifty thousand, fifty-one".